root/include/linux/sunrpc/svc_xprt.h

INCLUDED FROM

DEFINITIONS

1. unregister_xpt_user
2. register_xpt_user
3. svc_xprt_get
4. svc_xprt_set_local
5. svc_xprt_set_remote
6. svc_addr_port
7. svc_addr_len
8. svc_xprt_local_port
9. svc_xprt_remote_port
10. __svc_print_addr

/*
 * linux/include/linux/sunrpc/svc_xprt.h
 *
 * RPC server transport I/O
 */

#ifndef SUNRPC_SVC_XPRT_H
#define SUNRPC_SVC_XPRT_H

#include <linux/sunrpc/svc.h>

struct module;

struct svc_xprt_ops {
        struct svc_xprt *(*xpo_create)(struct svc_serv *,
                                       struct net *net,
                                       struct sockaddr *, int,
                                       int);
        struct svc_xprt *(*xpo_accept)(struct svc_xprt *);
        int             (*xpo_has_wspace)(struct svc_xprt *);
        int             (*xpo_recvfrom)(struct svc_rqst *);
        void            (*xpo_prep_reply_hdr)(struct svc_rqst *);
        int             (*xpo_sendto)(struct svc_rqst *);
        void            (*xpo_release_rqst)(struct svc_rqst *);
        void            (*xpo_detach)(struct svc_xprt *);
        void            (*xpo_free)(struct svc_xprt *);
        int             (*xpo_secure_port)(struct svc_rqst *);
        void            (*xpo_adjust_wspace)(struct svc_xprt *);
};

struct svc_xprt_class {
        const char              *xcl_name;
        struct module           *xcl_owner;
        struct svc_xprt_ops     *xcl_ops;
        struct list_head        xcl_list;
        u32                     xcl_max_payload;
        int                     xcl_ident;
};

/*
 * This is embedded in an object that wants a callback before deleting
 * an xprt; intended for use by NFSv4.1, which needs to know when a
 * client's tcp connection (and hence possibly a backchannel) goes away.
 */
struct svc_xpt_user {
        struct list_head list;
        void (*callback)(struct svc_xpt_user *);
};

struct svc_xprt {
        struct svc_xprt_class   *xpt_class;
        struct svc_xprt_ops     *xpt_ops;
        struct kref             xpt_ref;
        struct list_head        xpt_list;
        struct list_head        xpt_ready;
        unsigned long           xpt_flags;
#define XPT_BUSY        0               /* enqueued/receiving */
#define XPT_CONN        1               /* conn pending */
#define XPT_CLOSE       2               /* dead or dying */
#define XPT_DATA        3               /* data pending */
#define XPT_TEMP        4               /* connected transport */
#define XPT_DEAD        6               /* transport closed */
#define XPT_CHNGBUF     7               /* need to change snd/rcv buf sizes */
#define XPT_DEFERRED    8               /* deferred request pending */
#define XPT_OLD         9               /* used for xprt aging mark+sweep */
#define XPT_DETACHED    10              /* detached from tempsocks list */
#define XPT_LISTENER    11              /* listening endpoint */
#define XPT_CACHE_AUTH  12              /* cache auth info */
#define XPT_LOCAL       13              /* connection from loopback interface */

        struct svc_serv         *xpt_server;    /* service for transport */
        atomic_t                xpt_reserved;   /* space on outq that is rsvd */
        struct mutex            xpt_mutex;      /* to serialize sending data */
        spinlock_t              xpt_lock;       /* protects sk_deferred
                                                 * and xpt_auth_cache */
        void                    *xpt_auth_cache;/* auth cache */
        struct list_head        xpt_deferred;   /* deferred requests that need
                                                 * to be revisted */
        struct sockaddr_storage xpt_local;      /* local address */
        size_t                  xpt_locallen;   /* length of address */
        struct sockaddr_storage xpt_remote;     /* remote peer's address */
        size_t                  xpt_remotelen;  /* length of address */
        struct rpc_wait_queue   xpt_bc_pending; /* backchannel wait queue */
        struct list_head        xpt_users;      /* callbacks on free */

        struct net              *xpt_net;
        struct rpc_xprt         *xpt_bc_xprt;   /* NFSv4.1 backchannel */
};

static inline void unregister_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
{
        spin_lock(&xpt->xpt_lock);
        list_del_init(&u->list);
        spin_unlock(&xpt->xpt_lock);
}

static inline int register_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
{
        spin_lock(&xpt->xpt_lock);
        if (test_bit(XPT_CLOSE, &xpt->xpt_flags)) {
                /*
                 * The connection is about to be deleted soon (or,
                 * worse, may already be deleted--in which case we've
                 * already notified the xpt_users).
                 */
                spin_unlock(&xpt->xpt_lock);
                return -ENOTCONN;
        }
        list_add(&u->list, &xpt->xpt_users);
        spin_unlock(&xpt->xpt_lock);
        return 0;
}

int     svc_reg_xprt_class(struct svc_xprt_class *);
void    svc_unreg_xprt_class(struct svc_xprt_class *);
void    svc_xprt_init(struct net *, struct svc_xprt_class *, struct svc_xprt *,
                      struct svc_serv *);
int     svc_create_xprt(struct svc_serv *, const char *, struct net *,
                        const int, const unsigned short, int);
void    svc_xprt_enqueue(struct svc_xprt *xprt);
void    svc_xprt_put(struct svc_xprt *xprt);
void    svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt);
void    svc_close_xprt(struct svc_xprt *xprt);
int     svc_port_is_privileged(struct sockaddr *sin);
int     svc_print_xprts(char *buf, int maxlen);
struct  svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name,
                        struct net *net, const sa_family_t af,
                        const unsigned short port);
int     svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen);
void    svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *xprt);

static inline void svc_xprt_get(struct svc_xprt *xprt)
{
        kref_get(&xprt->xpt_ref);
}
static inline void svc_xprt_set_local(struct svc_xprt *xprt,
                                      const struct sockaddr *sa,
                                      const size_t salen)
{
        memcpy(&xprt->xpt_local, sa, salen);
        xprt->xpt_locallen = salen;
}
static inline void svc_xprt_set_remote(struct svc_xprt *xprt,
                                       const struct sockaddr *sa,
                                       const size_t salen)
{
        memcpy(&xprt->xpt_remote, sa, salen);
        xprt->xpt_remotelen = salen;
}
static inline unsigned short svc_addr_port(const struct sockaddr *sa)
{
        const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
        const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;

        switch (sa->sa_family) {
        case AF_INET:
                return ntohs(sin->sin_port);
        case AF_INET6:
                return ntohs(sin6->sin6_port);
        }

        return 0;
}

static inline size_t svc_addr_len(const struct sockaddr *sa)
{
        switch (sa->sa_family) {
        case AF_INET:
                return sizeof(struct sockaddr_in);
        case AF_INET6:
                return sizeof(struct sockaddr_in6);
        }
        BUG();
}

static inline unsigned short svc_xprt_local_port(const struct svc_xprt *xprt)
{
        return svc_addr_port((const struct sockaddr *)&xprt->xpt_local);
}

static inline unsigned short svc_xprt_remote_port(const struct svc_xprt *xprt)
{
        return svc_addr_port((const struct sockaddr *)&xprt->xpt_remote);
}

static inline char *__svc_print_addr(const struct sockaddr *addr,
                                     char *buf, const size_t len)
{
        const struct sockaddr_in *sin = (const struct sockaddr_in *)addr;
        const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)addr;

        switch (addr->sa_family) {
        case AF_INET:
                snprintf(buf, len, "%pI4, port=%u", &sin->sin_addr,
                        ntohs(sin->sin_port));
                break;

        case AF_INET6:
                snprintf(buf, len, "%pI6, port=%u",
                         &sin6->sin6_addr,
                        ntohs(sin6->sin6_port));
                break;

        default:
                snprintf(buf, len, "unknown address type: %d", addr->sa_family);
                break;
        }

        return buf;
}
#endif /* SUNRPC_SVC_XPRT_H */